As others have said, he knew you were willing because of you liking him. He just exploited that and took advantage of this. Is this right of him? No, absolutely not, and he should feel what it feels like to be taken advantage of. But honestly should you beat yourself up about it, personally I think not. You gave it your all, you liked him, and you did everything in your power at the time to show that you liked him, and to show that you trust him. He took it differently, and apparently does not like you. Thank god that this was not your first time, as your thoughts of him would have been much, much worse. If I was in your shoes, I would take him out of your life, and move on.

As nice as it would be to warn others, I too believe that its just going to complicate your life, and give you burdens that are unnecessary.